Exemplary embodiments of this invention generally relate to an integrated drive generator, and more particularly, to a variable shaft of a hydraulic unit of an integrated drive generator.
Aircrafts currently rely on electrical, pneumatic, and hydraulic systems for secondary power. A typical electrical system utilizes an integrated drive generator (IDG) coupled to each engine to provide a fixed frequency power to the distribution system and loads. One type of IDG includes a generator, a hydraulic unit, and a differential assembly arranged in a common housing. The differential assembly is operably coupled to a gas turbine engine via an input shaft. The rotational speed of the input shaft varies during the operation of the gas turbine engine. The hydraulic unit cooperates with the differential assembly to provide a constant speed to the generator throughout engine operation.
Due to packaging constraints, components of the hydraulic unit, such as nested, coaxial, variable and fixed shafts must be redesigned.